Here's the issue- it always cranks but sometimes it'll start up but not really, either way it will not run even when it acts like it's going to start. In the beginning it was very intermittent and only in cold weather if we stuck it in a shop over night it was fine but it progressed to get worse.
new parts are-
F/P
Distributor
F/P relay
Spider and Reg
Crank Sensor
Plugs
Wires
Coil
Ignition Control Module
Even hooked up a computer out of one of the other trucks we have and it does the same thing, all new ground cables. Blue spark, 60 psi of fuel. The codes haven't been checked in some time but the last time I messed with it, it only had a couple abs codes. So any advanced gurus got a idea? I don't believe there is a fuel pump control module on these older ones nor a bcm. So I'm just kinda out of ideas.

 

i know you replaced the grounds but did you clean the contacts? not 100% on the motor youre working on but does it have camshaft position sensor?

 

Yes it was a complete brand new distributor from GM itself camshaft position sensor is internal on it this is a 5.7. And yes all contacts were cleaned, however I'm thinking about changing engine harness next.

 

If it starts right up using a little starting fluid or brake cleaner then it may not be getting a injector squirt when you turn ignition on. If it doesn't fire right up using a cheater fluid then it could be a connection. I always use a stiff wire brush and dielectric grease even on grounds. Ecm grounds too. Extend a wire on multimeter with audible to check wires on harness before you replace it. Had one small ground burn thru before hooked up a big ground to starter bolt